| 摘要 |
<p>An apparatus and method for preventing pressure within at least a portion 64 of a conduit from increasing above a predetermined value. The device comprises a venting valve 10 having an inlet 12 and an outlet 14 and is selectively actuable between a closed configuration and an open configuration allowing venting from a biased closed main valve cylinder 77. The device also comprises controlling means 22, 32 comprising a first surface 24 exposed to fluid from a hydraulic supply, e.g. for a further application, and a second surface 34 exposed to fluid from the conduit. The first and second surfaces are arranged in opposing relation and the respective surface areas are selected such that the venting means is actuable to the vent configuration when the pressure in the conduit increases above a predetermined value. Used in oil and gas pipeline as HIPPS device to limit maximum downstream pressure and allow a thinner downstream pipe.</p> |
